1. Field of the Invention
The present invention relates to the field of electronic components particularly suitable for high frequency circuits used in electronic apparatuses, such as for mobile communications, their manufacturing methods, and radio terminals using these types of electronic components. More particularly, the present invention relates to electronic components provided with a conductive film on an insulated substrate, and radio terminals using such electronic components.
2. Description of the Prior Art
FIG. 17 is a side view of a conventional inductor element. The conventional inductor element comprises a quadratic prism or cylindrical substrate 1, a conductive film 2 formed on the substrate 1, a groove 3 created on the conductive film 2, and a protective material 4 made of an electro-deposited film laminated on the conductive film 2.
These types of electronic components are given predetermined characteristics by adjusting the spacing between the grooves 3.
The Japanese Laid-open Patents Nos. H7-307201, H7-297033, H5-129133, H1-238003, H5-299250, and H7-297033; and Utility Model Laid-open Publication No. S57-117636 disclose conventional electronic components. However, the mountability or electrical characteristics of the conventional electronic components may degrade if their size reduce. In addition, when forming the protective material 4 with an electro-deposited film, stress may be applied to the conductive film 2 through the electro-deposited film during manufacturing or when mounting the electronic component because the mechanical strength (rigidity) of the electro-deposited film itself is small. This may result in breaking of the conductive film 2, thus degrading the characteristics of the electronic component. In particular, when the conductive film 2 is coiled, the use of electro-deposited film for the protective material 4 has a significant detrimental effect such as short circuiting and breaking of the coiled conductive film 2. With even smaller electronic components being demanded in response to miniaturization of recent apparatuses, this problem is becoming more acute.
An electronic component of the present invention comprises a substrate, a conductive film disposed on the substrate, a groove created on the conductive film, and a pair of terminals disposed on both ends of the substrate. A length L1 of the electronic component in a direction toward the pair of terminals (a lengthwise direction) and length P5 and P6 of cross sections in the lengthwise direction of the pair of terminals satisfy the next relations:
0.07 less than P5/L1 less than 0.35
0.07 less than P6/L1 less than 0.35.
A radio terminal of the present invention employs the above electronic component of the present invention in at least one of a oscillating circuit, filter circuit, antenna, matching circuit between stages, and their peripheral circuits.